ISO INTERNATIONAL STANDARD 21159 First edition 2018-11 Ships and marine technology - Butterfly valves for use in low temperature applications Design and testing requirements Navires et technologie maritime - Robinets a papillon destinés aux applications a basse temperature - -Exigencesde conception etd'essai Get more free standards from Standard Sharing Group and our chats Reference number IS0 21159:2018(E) os1 @ IS0 2018 IS0 21159:2018(E) Contents Page Foreword .V 1 Scope .1 2 Normativereferences .1 3 Terms and definitions .2 4 Pressure-temperature rating .3 5 Structure. ..3 5.1 General 3 5.1.1 Structure 3 5.1.2 Materials 4 5.2 Design and materials of the body 4 5.2.1 Design .4 5.2.2 Materials 4 5.2.3 Manufacturing 4 5.3 Designandmaterialsoftheextendedbonnet 5 5.3.1 Design 5 5.3.2 Materials 5 5.4 Design and materials of the disc 5 5.4.1 Design 5 5.4.2 Materials 5 5.5 Design and materials of the stem 5 5.5.1 Design 5 5.5.2 Materials 6 5.6 Stem sealingee 6 5.7 Design and materials of the seat. 6 5.7.1 Design.. 6 5.7.2 Bore materials 6 5.8 Design and materials of the connection 7 5.8.1 Design 7 5.8.2 Materials 7 5.9 Requirementsofoperatingdeviceandactuators 7 5.10 Surface treatment. 7 5.11 Welding and heat treatment. 8 5.11.1 Welding 8 5.11.2 Heat treatment. 8 5.12 Repair welding. .8 6 Test and inspection .8 6.1 General 8 6.2 Material test 8 6.3 Non-destructive inspection. 8 6.3.1 General .8 6.3.2 Radiographic testing (RT) 9 6.3.3 Dye penetrant testing (PT) 9 6.3.4 Ultrasonic Testing (UT) .9 6.3.5 Retest 10 6.3.6 Submission of inspection results 10 6.4 Dimension check 10 6.5 Visual inspection 10 6.6 Heat treatment inspection 10 6.7 Operatingtests 10 6.8 Pressuretest 10 6.8.1 Pressure test in ambient temperature. 10 6.8.2 Test procedure and method. 11 @ IS0 2018 - All rights reserved iii IS0 21159:2018(E) 6.9 Fire-resistance test (if necessary) .11 6.10 Anti-static testing. 11 6.11 Cryogenic tests. .11 6.11.1 General. 11 6.11.2 Scope of tests .12 6.11.3 Test procedure. .12 6.11.4 Submissionoftestresults 13 7 Marking .13 Annex A (informative) Examples of butterfly valve construction. .14 Get more free standards from Standard Sharing Group and our chats iv @ IS0 2018 - All rights reserved